2011 Super Outbreak facts for kids

Quick facts for kids
2011 Super Outbreak

The storm system responsible for the historic tornado outbreak across the Southern United States on April 27
Meteorological history
Duration	April 25–28, 2011
Tornado outbreak
Tornadoes	360 tornadoes (Record for a continuous outbreak)
Maximum rating	EF5 tornado
Duration	3 days, 7 hours, 18 minutes
Highest winds	Tornadic – 210 mph (340 km/h) (Hackleburg–Phil Campbell) EF5 on April 27)
Lowest pressure	990 hPa (mbar); 29.23 inHg
Largest hail	4.5 in (11 cm) Saltville, Virginia on April 27
Overall effects
Fatalities	324 (+24 non-tornadic); 3,100+ injuries
Damage	$10.2 billion (Costliest on record for a tornado outbreak)
Areas affected	Southern, Midwestern, & Eastern United States
Part of the Tornadoes of 2011

The 2011 Super Outbreak was one of the biggest and most expensive tornado outbreaks ever recorded. It happened in the Southern, Midwestern, and Northeastern United States from April 25 to 28, 2011. This event caused a lot of damage.

Over 175 tornadoes hit Alabama, Mississippi, and Tennessee. These states were hit the hardest. Other powerful tornadoes struck Arkansas, Georgia, Kentucky, Louisiana, New York, and Virginia. Storms also affected other states in the Southern and Eastern U.S.

In total, 360 tornadoes were confirmed by the NOAA's National Weather Service (NWS) and Government of Canada's Environment Canada. These tornadoes touched down in 21 states, from Texas to New York and even southern Canada.

April 27 was the busiest day for tornadoes. A record 216 tornadoes touched down that day. Four of these tornadoes were rated EF5. This is the highest rating on the Enhanced Fujita scale. EF5 tornadoes are very rare, usually happening less than once a year.

Sadly, 348 people died because of this outbreak. This included 324 deaths directly from tornadoes. Another 24 deaths were caused by other thunderstorm events like strong winds, hail, flash flooding, or lightning. In Alabama alone, 238 people died from tornadoes. This outbreak was the most expensive tornado event in U.S. history. It caused about $10.2 billion in damage.

How the Storms Formed

The Super Outbreak happened because of a strong weather system. This system moved into the Southern Plains states on April 25. An extratropical cyclone (a type of low-pressure system) formed. It moved northeast, bringing bad weather with it.

On April 26, conditions were still dangerous. There was a high chance of severe thunderstorms. These storms could create strong, long-lasting tornadoes. The air had a lot of energy, which helps storms grow.

As the system moved east on April 27, a very powerful jet stream (fast winds high in the atmosphere) created strong wind shear. Wind shear is when winds blow in different directions or at different speeds at different heights. This helps tornadoes form. Temperatures were warm, from the 70s to 90s °F (mid-20s to 35 °C). This warm, moist air also fueled the storms.

The Storm Prediction Center (SPC) issued many warnings. They sent out 56 severe weather watches over four days. This included 41 tornado watches. Ten of these were "particularly dangerous situation" (PDS) watches. This means very strong tornadoes were expected.

April 25: First Tornadoes Strike

The SPC warned of severe storms from April 25 to 27. They issued a moderate risk for severe weather in states like Arkansas and Tennessee. On April 25, a PDS tornado watch was issued for Arkansas and nearby states.

Tornadoes were reported across several states that evening. Some caused serious damage in Arkansas. An intense supercell thunderstorm moved near Little Rock. A tornado emergency was declared for Vilonia. A large EF2 tornado hit Vilonia, causing severe damage and killing four people.

An EF3 tornado also struck the Hot Springs Village area. It caused a lot of damage and one death. Later, another EF2 tornado damaged a school and Little Rock Air Force Base. Heavy flooding also happened from the Red River valley to the Great Lakes. On April 25, 42 tornadoes were confirmed, leading to five tornado-related deaths.

April 26: More Storms Develop

On April 26, the SPC issued a high risk for severe weather. This was for parts of Louisiana, Arkansas, Oklahoma, and Texas. Conditions were perfect for extreme weather. A large PDS tornado watch was issued, meaning tornadoes were very likely.

Two main low-pressure systems caused storms. One moved northeast along the Mississippi River. Tornado watches were issued for the Lower Great Lakes. Two tornadoes touched down in Michigan, damaging farms. Further east, severe thunderstorms brought strong winds and large hail to Pennsylvania and New York.

The second low-pressure system formed in Texas and moved east. This created strong winds near the ground. It helped organize the supercell storms. Many tornadoes touched down in Texas, Louisiana, and Arkansas. Most were weak, but some caused a lot of damage. An EF2 tornado caused damage in Texas and Louisiana. An EF3 tornado destroyed buildings at Fort Campbell, Kentucky. On April 26, 55 tornadoes were confirmed, but thankfully, no one died.

April 27: The Most Active Day

The Storm Prediction Center (SPC)'s forecast for April 27, showing a high risk area in the Southern U.S.

Severe weather continued non-stop on April 27. For the second day in a row, the SPC issued a high risk for the Southern United States. They even increased the tornado probability to 45 percent for areas like Meridian, Mississippi, and Huntsville, Alabama. This is very rare. Conditions were extremely favorable for a major tornado outbreak.

Morning Storm Lines

Early on April 27, a cold front with low-pressure areas stretched from east Texas to the Ohio River Valley. Thunderstorms formed into a squall line (a line of thunderstorms). This line produced tornadoes from the evening of April 26 into the morning of April 27.

The squall line, with strong winds and many tornadoes, moved through Louisiana and Mississippi. Then it hit North and Central Alabama and parts of Middle and East Tennessee. The line grew stronger in Alabama due to moisture from the Gulf of Mexico and increasing wind shear.

Most tornadoes in this first line were weak. But some were strong and caused significant damage. An EF3 tornado damaged homes in Coaling, Alabama. EF2 and EF3 tornadoes caused severe damage and one death near Eupora, Mississippi. Another EF3 tornado heavily damaged downtown Cordova, Alabama. This town was hit again by an even stronger tornado later that day.

A storm cell produced 26 tornadoes as it moved northeast. One EF2 tornado hit Hanceville, killing one person. The initial storms caused widespread power and phone outages in Alabama and Tennessee. Some weather radio sites stopped working. This meant over a million people had no warning for later tornadoes.

Later in the morning, another squall line moved through northern Mississippi and Alabama. High wind shear and moisture continued. Several separate supercells formed along this line. They spawned seven weak tornadoes in northern Alabama around noon.

Afternoon Supercells Bring Violent Tornadoes

Extremely deep ground scouring near Philadelphia, Mississippi, caused by a fast-moving EF5 tornado that killed three people.

The most powerful supercells of the outbreak formed around midday in central Mississippi. They quickly grew stronger and produced very strong tornadoes. The SPC issued a PDS tornado watch at 1:45 p.m. CDT for Alabama, Mississippi, Tennessee, and Georgia. Many violent tornadoes started touching down rapidly.

By mid-afternoon, a tornado emergency was declared for Neshoba County, Mississippi. A large tornado was seen on the ground. This powerful EF5 tornado caused incredible damage northeast of Philadelphia, Mississippi. It tore pavement from roads and threw vehicles. The ground was scoured (dug out) up to 2 feet deep. Three people died when a mobile home was thrown 300 yards.

Another very long EF4 tornado passed near Enterprise, Mississippi. It killed seven people before moving into Alabama. Four tornadoes were officially rated EF5 that day. One EF5 tornado hit Smithville, Mississippi. Many brick homes were destroyed, trees were stripped of their bark, and an SUV was thrown onto a water tower.

The deadliest tornado of the outbreak was a long-tracked EF5 wedge tornado. It passed through rural Alabama and Tennessee. It completely destroyed towns like Hackleburg, Phil Campbell, Mount Hope, Tanner, and Harvest. This tornado killed 72 people. This was only the second time in history (after April 3, 1974) that more than two F5/EF5 tornadoes were reported on the same day.

Tornadoes continued through central Alabama into the early evening. A dangerous EF4 tornado struck Cullman, Alabama, around 3:00 p.m. CDT. It caused huge destruction downtown. Six people died, and 867 homes and 94 businesses were damaged or destroyed. Cordova, Alabama, already hit by an EF3, was struck by an EF4 tornado that killed 13 people.

Two violent EF4 tornadoes also ripped through Jackson County, Alabama. One killed a person near Bridgeport. The other passed near Pisgah and into Georgia, causing major damage in Trenton and killing 14 people.

Around 5:10 p.m. CDT, a very large and destructive tornado hit Tuscaloosa, Alabama. About 40 minutes later, the same tornado struck the northern suburbs of nearby Birmingham. A tornado emergency was issued for both cities. This tornado killed 64 people and caused huge damage in populated areas. It hit some of the same communities as past F4/F5 tornadoes in 1956, 1977, and 1998.

The supercell that made the Tuscaloosa/Birmingham tornado also produced another EF4 tornado later. This one killed 22 people in the Ohatchee, Alabama, area and moved into Georgia. Further south, a mile-wide EF3 tornado killed 7 people in rural areas and damaged Eoline. The final EF5 tornado of the day caused incredible damage in and around Rainsville, Alabama, killing 25 people.

Tornadoes kept touching down in Georgia as the sun set. This included a long-tracked EF4 tornado that caused major damage in Ringgold, Georgia, Apison, Tennessee, and Cleveland, Tennessee. It killed 20 people. After dark, violent tornadoes continued. A nighttime EF4 tornado destroyed many lakeside homes at Lake Martin in eastern Alabama, killing seven people. Strong nighttime tornadoes also hit Georgia, including EF3s that killed people in Barnesville and at Lake Burton.

Storms Continue East

Powerful tornadoes also hit Tennessee that evening. A violent EF4 struck New Harmony, Tennessee, leveling homes and killing four people. Two EF3 tornadoes crossed paths in Greene and Washington counties, causing eight deaths. A very large EF4 tornado leveled a mile-wide path of forest in Great Smoky Mountains National Park.

Another area of severe weather developed in Virginia, Maryland, Pennsylvania, and New York. Many tornadoes touched down here, mostly weak. However, an EF2 tornado near Halifax, Virginia, severely damaged homes and caused one death. Tornado alerts were also issued for Southern Ontario, Canada. One tornado was confirmed in Fergus, Ontario.

SPC Storm Reports for April 27

In Alabama, 238 tornado-related deaths were confirmed. Damage and power outages in Huntsville were so bad that over 650,000 people lost power. The EF5 tornado that hit Hackleburg and Phil Campbell damaged major power lines. Some areas were without power for two weeks.

The Storm Prediction Center received 292 tornado reports in 24 hours. April 27 set a record for most tornadoes in a calendar day (216). It also broke the record for most tornado touchdowns in any 24-hour period with 219. On April 27 alone, the National Weather Service in Huntsville, Alabama, issued 92 tornado warnings.

April 28: Final Tornadoes Dissipate

Tornado watches were issued for the Atlantic coast from Pennsylvania to Florida. Tornadoes were expected to be weaker and more spread out. However, the storms that started in the Mid-Atlantic and East Coast the night before grew stronger. They produced many tornadoes early in the morning.

A particularly active area was along the Interstate 81 corridor. This stretched from southwest Virginia, through the Shenandoah Valley, and into Pennsylvania and New York. This included a deadly EF3 tornado that hit Glade Spring, Virginia, very early. Three people died there.

Tornadoes were also reported in Florida, Georgia, South Carolina, North Carolina, and Maryland. Most of these were weak. Widespread flooding also hit the Midwest, South, and Eastern Seaboard. The last tornadoes of the outbreak touched down in eastern North Carolina. These were weak. The storm system moved out into the Atlantic Ocean that evening.

Tornado Statistics

* One tornado touched down in Ontario, Canada, on April 27 and was rated as an F0. It is counted as an EF0 in this table.

A record 360 tornadoes touched down over four days. 37 of these were EF3 or stronger. Four tornadoes were rated EF5. This is second only to the 1974 Super Outbreak (which had 7 F5s). Several strong tornadoes on April 27 traveled for very long distances, over 60 miles. Many tornadoes that afternoon came from supercells moving across Mississippi, Alabama, Tennessee, and Georgia.

Major Tornadoes and Their Impact

The outbreak included several extremely powerful and deadly tornadoes. Here are some of the most significant ones:

The Hackleburg–Phil Campbell–Tanner–Harvest, Alabama/Huntland, Tennessee Tornado

Hackleburg–Phil Campbell–Tanner–Harvest, Alabama/Huntland, Tennessee

EF5 damage in Phil Campbell, with homes swept away and grass scoured from hillsides.
Meteorological history
Duration	2 hours, 35 minutes
Formed	April 27, 2011, 3:05 p.m. CDT (UTC−05:00)
Dissipated	April 27, 2011, 5:40 p.m. CDT (UTC−05:00)
EF5 tornado
on the Enhanced Fujita scale
Highest winds	210 mph (340 km/h)
Overall effects
Casualties	72 fatalities, 145+ injuries

This was the deadliest tornado of the entire outbreak. It was a devastating, long-tracked, violent EF5 wedge tornado. It touched down in Marion County, Alabama, around 3:00 p.m. CDT on April 27. It caused massive damage along its path.

The tornado reached the Hackleburg area, leveling many homes and businesses. Hackleburg High School was destroyed. Well-built homes were completely swept away from their foundations. Cars were thrown hundreds of yards. About 75 percent of the town was destroyed. This was the first F5/EF5 tornado in Alabama since 1998.

Soon after, the town of Phil Campbell was also devastated. Many homes, even well-built ones, were swept away. At least three churches were badly damaged, with one completely destroyed. Mobile homes were destroyed and tossed far away. Cars were thrown and destroyed, with one wrapped around a tree. A 25-foot section of pavement was even torn from a road.

The tornado continued into Lawrence County, hitting Mount Hope. It caused major damage to homes and a restaurant. Nothing but the foundation was left of the restaurant. The tornado then crossed into Limestone County, coming close to the Browns Ferry Nuclear Power Plant. It caused power outages and the plant had to shut down.

Large area of pavement scoured from a road in Phil Campbell.

The tornado then hit Tanner, causing widespread EF4 damage and some near-EF5 damage. It destroyed a Doppler weather radar in Huntsville. It continued into Madison County, hitting the populated areas of Harvest and Toney. Hundreds of homes were damaged or destroyed. Many homes were reduced to rubble. A Piggly Wiggly grocery store was completely destroyed in Harvest.

The tornado then moved into Tennessee near Huntland. It caused mostly minor damage there, but some cinder block buildings were heavily damaged. The tornado eventually ended east of Huntland.

In total, this tornado killed 72 people, all in Alabama. This made it the deadliest single tornado ever to strike Alabama. It was also the longest-tracked tornado of the outbreak, traveling 132 miles.

The Tuscaloosa–Birmingham, Alabama Tornado

Tuscaloosa–Birmingham, Alabama

The demolished Chastain Manor apartment complex in Alberta City, Tuscaloosa.
Meteorological history
Duration	1 hour, 31 minutes
Formed	April 27, 2011, 4:43 p.m. CDT (UTC−05:00)
Dissipated	April 27, 2011, 6:14 p.m. CDT (UTC−05:00)
EF4 tornado
on the Enhanced Fujita scale
Highest winds	190 mph (310 km/h)
Overall effects
Casualties	64 fatalities, ~1,500 injuries

A large, multiple-vortex wedge tornado touched down in rural Greene County, Alabama. It then moved across Tuscaloosa County, hitting the southern and eastern parts of Tuscaloosa around 5:10 p.m. CDT on April 27. Debris from the tornado was reported falling in Birmingham, over 20 miles away.

Television cameras captured live footage of the tornado as it struck Tuscaloosa. Many homes and apartment buildings were destroyed. Businesses and a shopping center in Alberta City were completely leveled. Additional EF4 damage happened in Holt, a Tuscaloosa suburb, where homes were leveled or swept away. The tornado then moved through dense forest towards Birmingham.

Radar reflectivity and velocity image of the supercell that produced the tornado at 22:10 UTC (5:12 p.m. CDT) as it struck Tuscaloosa, with a debris ball clearly visible.

The University of Alabama closed its campus. All final exams were cancelled for the semester. The university itself was not damaged, but six students died.

The tornado then moved east-northeast across the western and northern suburbs of Birmingham around 6:00 p.m. CDT. It became very strong and wide. Suburbs like Concord and Pleasant Grove were devastated, with entire neighborhoods flattened. The tornado then weakened but still caused heavy damage in McDonald Chapel and Pratt City. It then hit Fultondale before ending north of Tarrant.

This violent tornado traveled 80.7 miles. Its widest point was 1.5 miles. It was rated EF4 with winds around 190 mph. In Tuscaloosa, 44 people died, and another 20 died in Birmingham. In total, this tornado killed 64 people and injured over 1500. President Barack Obama and First Lady Michelle Obama visited Tuscaloosa on April 29. President Obama said he had "never seen devastation like this."

Other Effects of the Storms

Rainfall totals within the United States for the week ending during the morning of April 29, 2011, which shows the extent of the heavy rain event this cyclone contributed towards.

This storm system also caused a lot of rain. Heavy rainfall totals reached over 19 inches in Arkansas. Thunderstorms with strong winds up to 80 mph hit parts of Ohio, uprooting trees and damaging roofs. Heavy flooding was reported in the Syracuse area. Interstate 81 was briefly shut down due to flooding.

In central and northern Arkansas, up to 10.44 inches of rain fell. This caused flash flooding that killed five people. In Monroe, Louisiana, flash flooding killed two people after an apartment complex was flooded.

Severe thunderstorms were reported as far north as Northern Ontario, Canada. Heavy rains and minor flooding also happened in Northern Ontario. Windstorms in Southern Ontario and Southern Quebec caused injuries, one death, damage, and power outages.

Other deaths were caused by straight-line winds. These happened in McComb, Mississippi, Moody, Alabama, Vestavia Hills, Alabama, and Franklin, Tennessee.

Aftermath and Recovery

Alabama Governor Robert J. Bentley declared a state of emergency on April 27. States of emergency were also declared in Arkansas, Kentucky, Mississippi, Missouri, Tennessee, and Oklahoma. After the tornadoes, President Barack Obama approved a federal emergency declaration for Alabama. This provided federal help, including search and rescue teams.

More than 2,000 National Guard troops were sent to Alabama. They helped with search and rescue. President Obama visited the affected areas of Alabama on April 29. He also approved a federal disaster declaration for seven Mississippi counties.

Power Outages

The storms severely damaged the Tennessee Valley Authority (TVA)'s power grid. Over 300 tall power transmission towers were destroyed. Some were "twisted like bow ties." These towers supported lines that brought power to 128 local distributors.

Transmission tower bent near Huntsville, Alabama.

TVA lost the ability to send power from both Browns Ferry Nuclear Power Plant and Widows Creek Fossil Plant. Both plants had to shut down. The nuclear plant used diesel generators for four days. About 60 percent of the warning sirens around Browns Ferry were disabled. The plant had to plan to use cars with loudspeakers to warn residents if there was another problem.

Huntsville was the largest city without electricity from TVA. All traffic lights were off, and a curfew was put in place. Power was slowly restored to Huntsville. Most localized outages were fixed eight days after the storm. The power outage caused problems with water treatment, stores, and buying gas and food.

Power outages in Ontario were minor. They were mostly caused by windstorms on April 28. Power was restored by the end of that day.

Images for kids

• 

  Remains of a mobile home that was destroyed by the tornado in Vilonia, Arkansas.

• 

  A brick home that was leveled by the tornado in Philadelphia, Mississippi.

• 

  Damage to the First Methodist Church in downtown Cullman, Alabama.

• 

  High-end EF4 damage to a home northwest of Arab, Alabama.

• 

  Aerial view of the damage path through Cordova, Alabama, from the west.

• 

  EF5 damage to a large, well-built home in Smithville, Mississippi.

• 

  Aerial view of damaged homes and businesses in Trenton, Georgia.

• Fackler–Stevenson–Bridgeport, Alabama/Haletown, Tennessee.jpg

  Concrete steps that were ripped from the foundation of a house in Bridgeport, Alabama.

• 

  Low-end EF3 damage to a brick home northeast of Sawyerville, Alabama.

• 

  Damage to the Volunteer Fire Station in Eoline, Alabama.

• 

  The EF4 Enterprise tornado, as it was in southeast Mississippi.

• 

  Low-end EF4 damage to a home near Enterprise, Mississippi.

• 

  A school bus stripped down to its chassis in Rainsville, Alabama.

• 

  An obliterated home along Skaggs Road in Rainsville, Alabama.

• 

  The Shoal Creek Valley/Ohatchee EF4 tornado.

• 

  A home swept off its foundation along Robins Mill Road in Shoal Creek Valley, Alabama.

• 

  EF4 damage in a subdivision at the north edge of Ringgold, Georgia.

• 

  EF4 damage to a large brick home in Apison, Tennessee.

See also

In Spanish: Oleada de tornados en Estados Unidos del 25-28 de abril de 2011 para niños

• List of North American tornadoes and tornado outbreaks
• List of F5 and EF5 tornadoes
• List of F4 and EF4 tornadoes
  • List of F4 and EF4 tornadoes (2010–2019)
• Tornadoes of 2011
• List of disasters in the United States by death toll
• Tornado records
• Tri-State Tornado – Deadliest tornado in North America, and made March 18, 1925, the deadliest tornado day recorded in United States.
• 1932 Deep South tornado outbreak – Deadliest tornado outbreak in Alabama history, including an F4 tornado that tracked through Tuscaloosa.
• 1936 Tupelo–Gainesville tornado outbreak – Infamous tornado outbreak occurring on April 5–6, 1936. Deadliest U.S. tornado outbreak since the March 1925 (Tri-State Tornado) outbreak, thus surpassing the March 1932, April 1974, and April 2011 outbreaks in total fatalities.
• April 1956 Birmingham tornado – F4 tornado that hit the northern Birmingham suburbs on April 15, 1956.
• 1974 Super Outbreak – Infamous tornado outbreak that occurred on April 3–4, 1974, similar in severity to the 2011 Super Outbreak; though the 2011 event surpassed the 1974 Super Outbreak as the largest recorded outbreak.
• April 1977 Birmingham tornado – F5 tornado that hit the northern Birmingham suburbs on April 4, 1977.
• 1994 Palm Sunday tornado outbreak – March 27, 1994, outbreak that produced an F4 tornado in St. Clair, Calhoun and Cherokee Counties in north-central Alabama.
• April 1998 Birmingham tornado – F5 tornado that struck western parts of Birmingham on April 8, 1998.
• December 2000 Tuscaloosa tornado – F4 tornado that hit southeast suburbs of Tuscaloosa on December 16, 2000.